Apart from chlorophyll, algae have several other pigments in their chloroplast. What pigments are found in blue,green, red and brown algae, that are responsible for their characteristic colours?
All photosynthetic organisms contain one or more organic pigments that are capable of absorbing visible radiations, which will initiate the photochemical reaction of photosynthesis. Three major classes of pigments found in plants and algae are the chlorophylls, the carotenoid and the phycobilins.
Carotenoid and phycobilins are called accessory pigments since the quanta (packets of light) absorbed by these pigments can be transferred to chlorophyll.
The diversity of light harvesting pigments in alga implies that the common ancestor was primitive and that no close affinity exists between blue, green, red, brown, golden brown and green algae, to use their common names.
The characteristic pigments of different classes are mentioned below
ClassCommon NameMajor PigmentsChlorophyceaeGreen algaeChlorophyll−a and Chlorophyll−b.PhaeophyceaeBrown algaeChlorophyll−a, Chlorophyll−c,Fucoxanthin.RhodophyceaeRed algaeChlorophyll−a, Chlorophyll−d,Phycoerthrin.